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	Accelerated vegetative growth measured by gross primary productivity in China from 1980 to 2018 期刊论文 OAI收割 ECOLOGICAL INDICATORS, 2023, 卷号: 154, 页码: 110704 作者: Zuo, Chan; Wang, Junbang; Zhang, Xiujuan; Watson, Alan E. \| 收藏 \| 浏览/下载：30/0 \| 提交时间：2023/09/07 Gross primary productivity Periodic oscillations Long-term trend Vegetation response Climate impacts
	Synchronous X-ray/Optical QPOs from the Black Hole LMXB MAXI J1820+070 期刊论文 OAI收割 Monthly Notices of the Royal Astronomical Society, 2021 作者: HXMT \| 收藏 \| 浏览/下载：52/0 \| 提交时间：2022/02/08 black hole physics Low Mass X-ray Binaries accretion accretion discs stars: individual (MAXI J1820+070) Astrophysics - High Energy Astrophysical Phenomena Abstract: We present high-speed optical photometry from SAAO and SALT on the black hole LMXB MAXI J1820+070 (ASSASN-18ey), some of it simultaneous with NICER, Swift and Insight-HXMT X-ray coverage. We detect optical Quasi-Periodic Oscillations (QPOs) that move to higher frequencies as the outburst progresses, tracking both the frequency and evolution of similar X-ray QPOs previously reported. Correlated X-ray/optical data reveal a complex pattern of lags, including an anti-correlation and a sub-second lag that evolve over the first few weeks of outburst. They also show correlated components separated by a lag equal to the QPO period roughly centered on zero lag, implying that the inter-band variability is strongly and consistently affected by these QPOs at a constant phase lag of roughly ±Ю The synchronisation of X-ray and optical QPOs indicates that they must be produced in regions physically very close to each other we thus propose that they can be explained by a precessing jet model, based on analogies with V404 Cyg and MAXI J1348-630.
	Detection of Flare Multiperiodic Pulsations in Mid-ultraviolet Balmer Continuum, Lyl Hard X-Ray, and Radio Emissions Simultaneously 期刊论文 OAI收割 The Astrophysical Journal, 2021, 卷号: 921, 页码: 179 作者: HXMT \| 收藏 \| 浏览/下载：24/0 \| 提交时间：2022/02/08 Solar flares Solar oscillations Solar ultraviolet emission Solar x-ray emission Solar radio emission 1496 1515 1533 1536 1522 Astrophysics - Solar and Stellar Astrophysics Abstract: Quasi-periodic pulsations (QPPs), which usually appear as temporal pulsations of the total flux, are frequently detected in the light curves of solar/stellar flares. In this study, we present the investigation of nonstationary QPPs with multiple periods during the impulsive phase of a powerful flare on 2017 September 6, which were simultaneously measured by the Hard X-ray Modulation Telescope (Insight-HXMT), as well as the ground-based BLENSW. The multiple periods, detected by applying a wavelet transform and Lomb-Scargle periodogram to the detrended light curves, are found to be ~20-55 s in the Ly`and mid-ultraviolet Balmer continuum emissions during the flare impulsive phase. Similar QPPs with multiple periods are also found in the hard X-ray emission and low-frequency radio emission. Our observations suggest that the flare QPPs could be related to nonthermal electrons accelerated by the repeated energy release process, i.e., triggering of repetitive magnetic reconnection, while the multiple periods might be modulated by the sausage oscillation of hot plasma loops. For the multiperiodic pulsations, other generation mechanisms could not be completely ruled out.
	Magnetotransport signatures of Weyl physics and discrete scale invariance in the elemental semiconductor tellurium 期刊论文 OAI收割 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2020, 卷号: 117 作者: Zhang, Nan; Zhao, Gan; Li, Lin; Wang, Pengdong; Xie, Lin \| 收藏 \| 浏览/下载：40/0 \| 提交时间：2020/11/26 Weyl semiconductor tellurium negative longitudinal magnetoresistance planar Hall effect log-periodic oscillations
	Timing analysis of Swift J1658.2-4242's outburst in 2018 with Insight-HXMT, NICER and AstroSat 期刊论文 OAI收割 Journal of High Energy Astrophysics, 2019, 卷号: 24, 页码: 30-40 作者: HXMT \| 收藏 \| 浏览/下载：56/0 \| 提交时间：2022/02/08 Accretion accretion disks Black hole physics X-rays: binaries: Swift J1658.2-4242 Astrophysics - High Energy Astrophysical Phenomena Abstract: We present the observational results from a detailed timing analysis of the black hole candidate Swift J1658.2-4242 during its 2018 outburst with the observations of Hard X-ray Modulation Telescope (Insight-HXMT), Neutron Star Interior Composition Explorer (NICER) and AstroSat in 0.1-250 keV. The evolution of intensity, hardness and integrated fractional root mean square (rms) observed by Insight-HXMT and NICER are presented in this paper. Type-C quasi-periodic oscillations (QPOs) observed by NICER (0.8-3.5 Hz) and Insight-HXMT (1-1.6 Hz) are also reported in this work. The features of the QPOs are analyzed with an energy range of 0.5-50 keV. The relations between QPO frequency and other characteristics such as intensity, hardness and QPO rms are carefully studied. The timing and spectral properties indicate that Swift J1658.2-4242 is a black hole binary system. Besides, the rms spectra of the source calculated from the simultaneous observation of Insight-HXMT, NICER and AstroSat support the Lense-Thirring origin of the QPOs. The relation between QPO phase lag and the centroid frequency of Swift J1658.2-4242 reveals a near zero constant when < 4Hz and a soft phase lag at 6.68 Hz. This independence follows the same trend as the high inclination galactic black hole binaries such as MAXI J1659-152.
	The Temporal Phenomena of Black Hole Transient XTE J1650-500 in Its 2001-2002 Outburst 期刊论文 OAI收割 CHINESE ASTRONOMY AND ASTROPHYSICS, 2018, 卷号: 42, 期号: 1, 页码: 48-68 作者: Chen Li; Lu Yu; Yan Lin-li; Li Zi-jian; Qu JL(屈进禄) \| 收藏 \| 浏览/下载：20/0 \| 提交时间：2019/09/24 X-rays binaries accretion accretion disks quasi-periodic oscillations time lags
	Oscillation Phenomena in the Disk around the Massive Black Hole Sagittarius A* 期刊论文 OAI收割 PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, 2011, 卷号: 63, 期号: 5, 页码: 1093-1116 作者: Miyoshi, Makoto; Shen, Zhi-Qiang; Oyama, Tomoaki; Takahashi, Rohta; Kato, Yoshiaki 收藏 \| 浏览/下载：45/0 \| 提交时间：2015/08/19 accretion black hole physics quasi-periodic oscillations radio: individuals (Sagittarius A*) accretion disks
	Temporal and spatial characteristics of wet-dry climate variation in the northern slope of Tianshan Mountains, Xinjiang 会议论文 OAI收割 Proceedings of SPIE - The International Society for Optical Engineering, Guangzhou, China, 2008 Yu; Meiyan1; 2; Chenxi; C.1; Bao; Anming1 收藏 \| 浏览/下载：20/0 \| 提交时间：2011/08/23 Geographic information systems - Landforms - Time series - Wavelet analysis - Wavelet transforms - Abrupt changes - Climate variation - Correlation analysis - Desert areas - Different time scale - Enso - Influence degrees - Mexican hat wavelets - Multi-time scale - Northern slope of tianshan mountains - Periodic oscillations - Rainfall datum - Regional characteristics - Research results - Temporal and spatial characteristics - Xinjiang
	Electronic states of a two-dimensional electron system in a lateral superlattice and a perpendicular magnetic field 期刊论文 OAI收割 physical review b, 1997, 卷号: 56, 期号: 24, 页码: 15744-15751 Wu XG 收藏 \| 浏览/下载：45/0 \| 提交时间：2010/08/12 QUASI-CLASSICAL CALCULATION QUANTUM-DOT ARRAYS MAGNETORESISTANCE OSCILLATIONS COLLECTIVE EXCITATIONS BAND-STRUCTURE PERIODIC POTENTIALS WAVE-FUNCTIONS GAS MODULATION MAGNETOTRANSPORT